This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The aim of this study is to determine the range and magnitude of the changes in scrotal temperature induced by laptop computer use, and evaluate the significance of these findings as risk factors for male infertility. This pilot study will facilitate further investigation of spermatogenetic and hormonal disorders associated with the use of laptop computers, and the possible development of a thermoprotective device.